Grinding art



Jan. 2,1923.

J. H. MACARTNEY ET AL.

GRINDING ARTl FILED sPT.3,1918.

2 SHEETS-SHEET l.

deck Macaw g.

Cai

or if ri al orare JOI-IN H. MACARTNEY AND JACK MACABTNEY, 0F LOSANGELES, CALIFORNIA.

eanvnrive Aer.

Application filed September 3, 1913. Serial No. 252,482.

To all LU/tom it may conce/m.' l

Be it known that we, donn H. lilAoiiiifrNnif and JACK lvlacanfiniir,both citizens ot the United States, residing at lios Angeles, in thecounty of Los Angeles and State ot California, have invented anddiscovered new and useful Improvements in the Grinding Art, ot which thefollowing is a specifica tion. l

This invention and discovery relates to the art of comminution,trituration and levigation, and includes a method and means adapted toreduction ot loose, broken materials to a required degree of lineness.

in object of this invention is to perform the required reduction,trituration or levigation with maximum ease and minimum ei;u pense, andin such a manner as to insure that the product of the triturating orlevigating process shall be practically tree from particles of theapparatus by which the triturating or levigating operation is effected.

This invention and discovery relates to the formation and maintenance otti'it'urating, grinding or pulverizing surfaces, and also to the methodwhereby the reduction of the broken material is effected.

The discovery and invention is regarded as broadly new, primary andbasic, in that centrifugal and other torces are combined in a practicalmanner to produce out ot brolien material of the character to bereduced, an instrument by which the power required for `the reductiveworli, brought into operation under conditions effective to suchreduction; and also in that the mode of effecting the grindinc`operation is such as to attain the desired' end oit constantly renewingand making most effective the grinding surfaces by which the reductionis to be accomplished,

W e have discovered that it is possible to 'produce out or loose brokenmatei'i l a rigid body constituting a practical grinder capable oi"cooperating with another grinder or another body to reduce to anydesired degree of lineness, material of the character ot which the saidbroken material is criniposed, and that this may beaccoinplished by setting up centrifugal torce through revolution of broken material 'at arequisite speed to generate sufficient centrifugal torce to holdthefinaterial outward subject to a restraining force operatingcontinuously coaxial to the axis and normal to the yplane ofrotationthereoic to form an annular fiat faced mass so that by aresolution oit forces 'the rigid `grinderis so formed out of thematerial that is supplied to be ground; and

4that by relatively rotating two of such by centrifugal torce, whichalso' effects the building up of an annular body composed oi the brokeninaterialxand having a revolv- 'body ot' brokenmaterial is held frictiontight y ingsurilace extending at right angles to the f axis ofrevolution. i

Where a plurality of such bodies are employed, a grinding operation maytakeplace between opposing surfaces oit suoli bodies provided saidbodies are non-synchronously rotated. l

By so arrangingthe peripheral restraining means so as to space thenon-synchronously revolving bodies a distance apart, a

peripheral discharge ywill be produced consisting oi" comminutedmaterial having a `lineness determinedby the separating space and alsoby the relative rotative speeds.

An object is to minimize the wear upon such mechanical means as may beemployed to apply power to the work oifreducing the y broken inateri alto' the'required linenes.

` Other objects, advantages and features of invention 'and discovery,may appear `trom the accompanying drawing, `the subjoined i detaildescription and appended claims.

The new method of pulverizing may be carried out in various ways; andvarious means and diiiierent forms of apparatus may be employed to thatend.

For the purpose of describing the saine, referente is made to theaccompanying drawings in which, l

Figure l; is an elevation in section online al `Fig. 2, intended toillustrate the carrying on of thc operations involved where two grindersare formed and caused. to coact.

Fig. 2A .is a view at right angles to Fig. l, as indicated by lineazz-iii saidliig. 1. Parts are broken 'away to expose interiorconstruction.

Fig.l Fig. 2, grinding. Y y f lll/ve' havey discovered that by a.relative 3 is an enlargeddetail fragment of with liner material in theprocess of iio regulated supplying oli, and setting` up centriiugaltorce within. the separate units o adapted to form an annular mass 7)olf broken loose material ot the character to be reduced to a greatertineness, and pe-A ripherally coifitining` the m in direct opposition tothe operation oit said centrifugal torce upon such units so as to gire ade'i'iuite cylindrical form to the annular mass, we are able to producea practically rigid and solid body having a flat continuous grindingsurface c and also hai/'ing a centrally located cavity d; and that byfeeding broken inaterial as at e, for further reductiona and torrenewing and maintaining the grinding surface; a reduction is eliiectedwith surdi cient speed and effectiveness; said flat tace being broughtinto opposition to a corresponding facecorrespondingly formed tor thepurpose of effecting the grinding.

ldlc have also discovered that upon opposing tivo ot such flat grindingsurfaces to each other, as at c c. within two containers l. 2, spacedapart a requisite slight distance, and supplying loose material ot thesame character to the cavity or chamber (Z formed within said containersat a distance inter nally, from the periphery ot the mass7 such suppliedmaterial will constantly renew both annular flat grinding surfaces thusconstituted7 as well as supply material to produce the requisiteproduct; with maximized cpeed and minimized enpemliture olf power.

The size of the interior chamber into which the t'resh broken materialmay be fed will enlarge or diminish according to the relative speeds offeeding and grinding. lncreasing the feed, decreases the cavity, andvice versa it the speed of the grinders remain constant.

@ur new method ot grinding or crushing loose or broken material includesutilizing a regulated teeihcentritugal torce and a torce counter theretoto gather such niaterial into, and hold such material in, a mass ormasses tlat faced and annular subjected to the rotative action by whichthe requisite centrifugal torce is generated. stood by reference to thedrawings in which l, 9., indicate hollow rotating heads containingmasses l), 7i. of broken material, the separate units d., ou which aresulriect to the action of centrifugal *force through the revolution otthe masses l1, l2. przu'tically about a, common locus wi bin the fieldor fields of revolution. The heads are shown asbeing revolved on axeset, 5, that are eccentrioto each other, so that the grinding faceswillbe relatively oscillated as well as relatively revolved. The regulatedfeed is indicated by the annular iorm of the masses.

The restraining or intercepting liorce which is opposed to thecentrifugal force may be a component of any character effective to thatend, and is indicated by the an- This may be under` Lari-idee nular rimwalls (i, 7, by which it is understood the 'terms oli the grindingsurfaces `will he determined. lllach surface will vary in 'form andshape depending upon the speed et revolution of the mass or massesconstitutii g such surface or surfaces. and said indingl surfaces at c.o, o'li the two revolving bodies 7i. oit broken material will be eXtended approximately equidistanti 'from a niedial plane between therevolving bodies ot material. The opposing Yfaces 8, 9, of' the rimwalls 6. 7, are spaced apart according to the lineness ot productdesired.

The peripheral restraining means represented by the rim walls may be oliany suitable character adapted to hold the material in opposition to thecentritugal l'orces set up in the two annular bodies respectively.

The two masses lo, b, are so placed that their grinding surfacescooperate to grind the material supplied to the interposed cavity orel'iamber within them.

ln the drawing, the masses are shown revolving on or about ahorizontal'axis indicated at 3, and conveyor means comprising a tubularshaft 10, and a screw conveyor ll., which elements are means indicatedtor the purpose of su pplying material :lroin a hopper l2, to a centralport 13, which located at or about the medial plane o't revolution sothat thematerial that is led into the chamber while said containbeing`revolved in opposite directions., will tale on motion immediately;whereby the broken i'naterial is put into a revolving state in twoannular masses, the constituents ot which brought under control oi'centrifugal Yforces that voperate at rightangles to 'the airis ofrevolution, with the result that n'iaterial beine' supplied to theinterior oi" the chamber lormed by the two containers Vtorms theoppositely rotating annular contacting vfaces that become triturated andground by the action oifthe rigid masses oit material and the interposedloose units upon each other, and to torni the central leed chamber.

rlhe material being thus delivered at the medial plane or the meetingplane between the two grinding faces thus formed, at once serves toaugment the grinding faces, and the innermost material will apply itoreeto the pieces or separate units olf material nearer the periphery todrive them directly outward; and, also. by the resolution olt torresg todrive suclivpieces or units :from one side` ol the medial plane towardsthe mass on the other side ol' such medial plane, and vice versa; sothat the centrifugal force not only acts to provide a practically solidand rigid grinding surface, but it also acts to cause the surfaces todeviate 'from a direction at right angles to the axis, so that at themedial plane near vthe periphery there isgrmding not only of' thesurfaces formed by the peripherz-illy restrained, centrifugallyvinipelled, pieces, but there also caused a grinding` action of pieceupon piece at the medial plane.

The peripheral restraining means shown, are in the form of annuli, fixedby webs. 14, l5, to the shafts el, 5, by which they are revolved.

Said webs form `enel walls to restrain the material from displacement indirections parallel to the axis.y of revolution and are spaced apartfrom the plane of the opposite faces of the rim wallslsuiiiciently toprovide the cavity necessary to accommodate the requisite grinding bodyor mass.

.ln the drawings the operation `is indicated as being performed in suchmanner that the centrifugal lines of force act in vertical planesthereby causing that distribution of the gravity fed material within thechamber or cavity inside the revolving bodies or masses, to occurwithout gravitational deflection from one to the other sideof themeeting or medial plane where the pulverikzation is effected. Thus thechamber 'formed within the mass contained Within the adjacentcontainers, and the distribution of the material to the field where itis given the rotary motion by which centrifugal force is generated andapplied to bring the material into a rigid and practically solid formand to impose upon the inass the character of solidity, is madesymmetrical and the operation is conducted with all the elements inproper balance.

The discharge of the line product thus also occurs in a vertical planeall around the riiu walls and such product may be collected by a housing16, `and therefrom' is gravitationally dischargedthrough the bottomoutlet 17, into any receiver, not shown.

By thus impelling under centrifugal force masses of broken material tobe pulverized, and restraining such material at a distance from thecenter of impulsion to form relatively revol. ing rigid bodies havingopposed grinding surfaces within containers the opposed rim walls ofwhich are spaced apart to allow discharge of fine inaterial only betweenthe outer rims of such grinding surfaces vand their containers, the

grinding is effected without attrition upon the apparatus by thematerial to be ground;

`and by .imposing upon the two bodies of material, fields of revolutionthat are eccentric to each other, a criss-cross rnblning effect issecured so as to avoid scoring effects.

iles the separate units are thus acted` upon by centrifugal force theyare caused to revolve or rotate more or .less upon their individualcenter or centers of gravity, thus to facilitate disintegration andpulverization.

By revolving the masses of broken material about a horizontal axis andfeeding fresh broken .material that is to be pulverized or reduced,centrallyy into said chamber,

are represented as consisting of brolren roelr` of an average size asmay be desired in reduction of ore, paint, clay or stone for any purposerequiring the material to be ground.

lullig. 3 the units a have been reducedr to a much greater lineness. J

The product is indicated at 18 and may in the nature of line dust if thegrinding is done dry or in the nature of suspensions if the grinding isdone wet. 2

' The speed of` revolution-imist be such to generate the requisitecentrifugal force.

Otherwise the work will not be effective'.

' il speed of from about 800 to`vl200 revolutions more or less perminute is'found to be effective, and the speed of the feed will be madeto correspond thereto, due consider.- tion being given to the characterof the material so as to. form theannular grinding surfaces according tothe principles herein'before set forth.

lille claims# f il. rlhe inethod y.of pulverizing material, whichconsists in impelling under `centrifugal force masses rof brokenmaterial to be pnlverizeihrand restraining` such material at a distancefrom the center of impulsionto form relatively revolving circular rigidbodiesliaving continuously opposed grinding surfaees'and allowing` thedischarge of line material only between the oiilter rims of suchsurfaces.y and supplying freshv material to said grinding surfaces atthe point of contact between such bodies.

2. ln the art of pulveriiaing material the method of forming a discgrinder rvliich consists in impelling under centrifugal force masses ofbroken material to be pulverized, and restrainingsuch material at adistance from 'the center of impulsion to form a revolving circularrigid body having its grinding` surface continuously in a planeperpendicular to its of rotation, and supplying Afresh material at thearial center ofthe medial plane `of said grinding siii'-` face.

3. The method of grinding or crushing loose or broken material byutilizing cen- 'trifuofal force and a force normal thereto to gathersuch material into and to hold it into annular' mass and causing thematerial of one annular mass to continuously grind against the materialof another similar mass, and supplying fresh material at the axialcenter of the medial plane of said annular masses.

4. The method of forming broken or loose material into a grinder whichconsists in subjecting such material to the actionv of centrifugal forcewithin a revolving. peripheral restrainer, and bringing a plurality ofsuch grinders into contact with each other while revolving so as to forma continuous grinding surface, and supplying fresh material at the axialcenter of the medial. plane of said grinding surface.

5. rllhe method of forming grinding apparatus out of loose or brokenrock or other material by subjecting such material to the action ofcentrifugal force and a force normal tiereto, forming a plurality ofrigid masses, and bringing a plurality of such masses into contact witheach whilel each is revolving on its own axis; so that such roei; orother material will be ground or crushed by action of component units ofone of such masses upon component units of another of such masses andthereby form a continuous grinding surface between said masses, andsupplying fresh material at the axial center of the medial pla-ne ofsaid rotating masses.

6. The method of grinding material substantially set forth whichcomprises subjecting two masses of said material to the action ofcentrifugal force, rest-raining said material in such a manner that eachof said masses forms a separate, continuous grinding surface, said twomasses being so placed that their grinding surfaces cooperate to grindthe material therebetween and snpplying fresh material to such masses attheir grinding surfaces.

7. The method set forth of grinding material which consists in revolvingtwo peripherally restrained masses of broken mateial about a commonaxis, the axis of revolution of each mass being horizontal, andtherebygenerating suliicient centrifugal force to form said bodies respectivelyinto annular grinders; spacing the adjacent faces of the grinders apartto allow fine material to pass out at the rim; and causing fresh brokenmaterial to pass to the bodies at the medial plane between such bodies.

S. The method set forth of grinding loose or broken material whichconsists in holding such loose or broken material by means ofcentrifugal force within two opposite revolving containers in such amanner that for all practical purposes a continual grinding action takesplace between the two masses of such material itself and not be- -tweensuch masses of material and their respective containers, and supplying`fresh broken material to said masses at ythe axial center of the medialplane of the rotating masses.

9. rlhe method substantially set forth of holding loose or brokenperipherally restrained material in place by centrifugal force so thatysuch loose or broken material may be continuously ground against asimilar mass of said material held in like manner so that neither masshas any grinding action upon its respective container and supplyingfresh material to said masses at the axial center of the medial plane ofsaid revolving masses.

10. 'lhe method set forth of grinding loose or broken material withinopposed containers in which the material to beground is held in placewithin such containers by ccntrifugal force in such manner ythat suchmaterial forms a protective lining for such containers and by the actionof such centrifugal force such material is gathered and formed intocrushing or grinding masses having annular faces which continuously actupon each other to crush or grind such material and supplying freshmaterialto said masses at the axial center of the medial plane of saidgrinding masses.

ll. The method of pulveriaing material, which consists in impellingunder centrifugal force broken material to be pulverized, res rainingsaid material at a distance from the center of impulsion into annularmasses to form said masses respectively into continuous annulargrinders; supplying fresh broken material at the axial center' of themedial plane between said masses and allowing the discharge of thepulverizcd material only between the outer rims of the restrainingmeans.

12,'The method of grinding material,

which consists of forming by entrifugal force two oppositely revolvingmasses of the material to be ground, which server as continuousgrinders; supplying fresh material. to said grinders at' the axialcenter ofthe medial plane of said masses, and allowing ground materialonly to peripherally pass out between said masses.

ln witness whereof, 'we have hereunto set our hands at Los Angeles,California, this 10th day of August, '1918.

JOHN H. MACARTNEY. JACK ItACAlRTNEY, lVitness:

Janus R. TowNsnxn.

